Modular concrete form system

ABSTRACT

A modular concrete form system which can also reduce the amount of concrete required, while producing a concrete surface that is equal to or stronger than the conventional construction processes. A matrix is provided having two sidewalls with a plurality of arched segments spaced apart by concave troughs. Multiple matrixes can be linked together to create extended lengths to be terminated at various locations by the means of the termination units. The curing time of the concrete is extended because less concrete is in contact with the surface and slowing the curing time of the concrete has the result of improving the quality and minimizing the cracking.

FIELD OF THE INVENTION

This application is a Continuation-in-Part Application from U.S. patent application Ser. No. 10/994,854 filed on Nov. 22, 2004, and currently pending. Molds are used to cast structures out of many types of materials. Typical structures, especially those related to construction, are cast as solid pieces. An example of such a process is the casting of structural concrete. The present invention relates to a new and unique process for the construction of concrete surfaces such as sidewalks, patios, slabs and the like. This process requires less concrete and produces a surface that is equal to or stronger than a concrete surface constructed in a conventional manner.

BACKGROUND OF THE INVENTION

The invention relates to the field of forming and placement of concrete surfaces. In particular, the present invention provides a novel modular concrete form system of construction where less concrete is used to produce a surface that is equal to or stronger than the conventional methods.

Concrete form and stake assemblies are conventionally employed extensively for the placement of concrete in order to shape and contain the concrete in the process of creating such things as sidewalks, driveways, patios, and slabs. Preparation of a site for the placement of concrete involves, after leveling the area and compaction, erecting a frame to contain the concrete. Erecting wood forms for concrete placement commonly involves the placement of stakes, attaching the form members to the stakes by nailing the form into place and ultimately forming a cavity within the completed assembly of forms into which concrete is placed. To cover a length larger than any one form, forms are abutted in a cooperative engagement, end-to-end, or side to side, or in both directions, to cover the additional length necessary. The concrete is placed into the cavity within this frame over the earthen surface. The surface of the concrete is finished and the frame is then removed once the concrete has set. In some construction projects, such as bridges or road structures, “pre-stressed” concrete is made by casting concrete around cables that are held at a tension. Because typical concrete structures are solid concrete (with the exception of the re-bar pieces), structure strength depends on the thickness of the concrete and the re-bar reinforcement. However, a solid structure is not necessarily the most efficient use of material volume and mass to achieve strength. For example, the base of a tall structure may need to support a great deal of weight, including its own. Thus, what is needed, is a method of casting materials in more efficient shapes, thereby saving material cost and mass, while providing a convenient method of forming structures.

Forms erected for the placement of concrete conventionally are constructed of lumber. Often, in order to accommodate the various dimensions of forms, the lumber must be cut to shorter lengths to accommodate specific projects, making it unlikely the lumber will be used on a subsequent project of differing dimensions. Further, the necessity of nailing or other means of attaching the wooden forms to the stakes results in damage to the lumber with the result being the lumber is likely consumed in the placement of one slab of concrete. Additionally, the price of lumber has increased greatly over the past few years. Furthermore, because concrete tends to stick to the wood, the wood forms cannot be removed at the end of the day. Instead, the worker must return on a second day to remove the forms after the concrete has sufficiently set up.

One solution to the drawbacks of wood forming is to provide a metal form that will not be consumed during one project and can therefore be used in subsequent projects. Traditionally, these metal forms were abutted end-to-end, as was the case with the wooden forms, to accommodate lengths longer than a single form board. However, the problem with such an assembly is that without specific lengths of metal forms, it is difficult to modify the form to accommodate the various lengths necessary to build an appropriate size frame. Metal forms are not practical for small projects due to the high initial costs.

Additional problems occur pouring concrete sidewalks and slabs when the concrete dries too rapidly. Workers should water the area where the concrete is going down prior to the pour, but if the ground is unusually absorbent or if the weather is excessively warm and the concrete loses its moisture content too fast it is more susceptible to cracking.

REFERENCES SITED

More recently, U.S. Pat. No. 6,705,582 of John Osborn presented an assembly of concrete forms for use in the placement of concrete having a pair of longitudinal form members and a ground engaging member that is in contact with at least one of the longitudinal form members. A first longitudinal form member slidably overlaps a second longitudinal form member such that the length of the combination of longitudinal form members is adjustable. Inverted U-shaped channels are provided at the top of each of the longitudinal form members that allows a male/female overlapping relationship and provides a location to receive the ground engaging member. To create an angle, a corner forming bar is provided for the assembly, extending between two of the longitudinal form members. A ground engaging member with a guide slot and locking mechanism is also provided for securing the longitudinal form members in place.

This patent describes a conventional style of concrete form where the surface is prepared and the forms are staked around the perimeter. Although it may save some time of installation, and is not constructed of wood, it does not offer the capability to reduce the amount of concrete required, and has no effect on the strength of the finished product.

U.S. Pat. No. 6,761,345 of Willy J. Reyneveld, describes a concrete form having a first wall defining a predetermined thickness and a peripheral edge of a concrete slab, and a second wall transverse to the first wall for supporting a temporary extended border portion of the slab having a thickness less than the predetermined thickness and such that an upper surface of the slab including the temporary extended border portion is substantially flat and continuous. A process for pouring and finishing a concrete slab having at least one peripheral edge and a predetermined thickness includes providing one or more concrete forms in an arrangement defining a periphery of the slab. The form has a recessed top wall providing a support area for a temporary extended border portion of the slab having a thickness less than the predetermined thickness. The concrete is poured within the area defined by the form to a height determined by an upper edge of the form so that the temporary extended border portion of the slab is supported on the recessed top wall. The method includes surface finishing the concrete slab across the top surface thereof, extending outwardly at least to the innermost portion of the temporary extended border portion of the slab. After the concrete has hardened, the form is removed along with the temporary extended border portion.

This patent describes a unique style of form primarily used in building slab construction and would not be of value in the construction of sidewalks or patio slabs. It offers no ability to reduce the amount of concrete used and has no effect on the strength of the finished product.

U.S. Pat. No. 6,021,994 of Michael E. Shartzer, Jr. teaches a flexible concrete form which can be arranged to provide both straight and curved configurations, and is adapted to flex both horizontally and vertically. The form includes a face panel and upper and lower flanges having lips on their back edges. An intermediate rib spaced below the upper flange provides a ledge on which a rigid core member can be installed to enhance the rigidity for straight areas. The upper and lower flanges have aligned openings for receiving stakes used to anchor the form to the ground. The form is preferably constructed from polyethylene, polyvinyl chloride, or polybutylene because of the strength and flexibility of these materials as well as their ability to release from concrete without the need for scraping or release agents.

This patent teaches of another sidewall type of concrete form that is staked around the perimeter of the desired area to retain the concrete when it is installed. None of these previous efforts, however, provides the benefits attendant with the present invention. The present invention achieves its intended purposes, objects and advantages over the prior art through a new and unique modular concrete form system.

In this respect, before explaining at least one embodiment of the invention in detail it is to be understood that the invention is not limited in its application to the details of construction and to the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.

As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for designing of other methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent construction insofar as they do not depart from the spirit and scope of the present invention.

OBJECTS OF THE INVENTION

An object of this invention is the provision of a device and method for paving.

An additional object of this invention is improving the curing of concrete employed in slabs, sidewalks, patios, and other pavement employing concrete set in forms.

The object of this invention is to simplify the process of constructing concrete sidewalks and slabs.

Another object of this invention is to reduce the quantity of concrete required on concrete projects like sidewalks and slabs.

Another object of this invention is to increase the strength of concrete sidewalks and slabs.

Another object of this invention is to retard the drying time of the concrete used on sidewalks and slabs.

Yet, another object of this invention is to decrease the preparation time required to construct concrete sidewalks and slabs.

A further object of this invention is to eliminate the requirement of coming back to a jobsite to remove the forms from the concrete sidewalks or slabs.

A final object of this invention is to reduce the costs involved in constructing concrete sidewalks and slabs.

The foregoing has outlined some of the more pertinent objects of the invention. These objects should be construed to be merely illustrative of some of the features that are more prominent and applications of the intended invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or by modifying the invention within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description of the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.

SUMMARY OF THE INVENTION

In some embodiments, one or more interior mold forms are used to displace material inside a structure being cast. The forms are shaped so as to provide structural integrity in the finished structure cast around them.

In other embodiments, an interior mold form having ridges running in one direction on one side is used to fill the center of a structure during casting. In some embodiments, the structure is cast from concrete and the form is made from polystyrene. In some embodiments, the form is set around a re-bar grid.

In additional embodiments, the interior mold form has a second set of ridges on its second side. In some embodiments, the second set of ridges runs in a cross-direction to the first. In some embodiments the ridges have semi-cylindrical or trapezoidal cross sections.

In other embodiments, the form is created by machining out semi-cylindrical ridges with flat walls, separated by troughs, on one side, then on the other side of a sheet of material. In some embodiments, small holes are bored for plastic inserts to hold the form in position. In some embodiments the form is held away from re-bar to allow concrete to flow around the re-bar.

In some embodiments, the resulting concrete structure, having crossed interior arch-like cells, provides strength equivalent to or greater than that of solid concrete, the displacement of concrete by the form saving weight and cost.

In some embodiments, a process of concrete casting includes laying down a layer of parallel re-bar, forming a 3-D polystyrene mold, and providing the mold with plastic spacers to hold it in correct alignment to the re-bar. The form is placed over the first layer of re-bar, a second layer of re-bar is added over the mold, and the re-bar intersections are attached together. The mold and re-bar are held between sides of a mold, and concrete is poured, and allowed to harden. The external mold sides are removed, and the internal form remains in the concrete structure.

In some embodiments, a mold form comprises an array of semi-spherical bumps.

In some embodiments, a mold is created from an exterior volume and an interior mold form.

In a particularly preferred embodiment of the disclosed device, there is a modular concrete form system that accomplishes its objectives by the use of a matrix constructed of polypropylene foam, polyethylene foam, expanded polystyrene (EPS), PVC foam, urethane foam, epoxy foam or any other foam suitable for the application. The foam matrix will consist of two sidewalls and a plurality of arched segments separated by concave troughs. The foam matrix will come in a variety of lengths with a modified tongue and groove or keyed means for interconnection to adjacent forms at the distal ends, to create as long a modular concrete form system as desired. The foam matrix can also be employed to create both longer and wider concrete forms by keying side edges also to engage adjacent cooperatively keyed edges. It must be understood at this time the explanation deals with a modified tongue and groove or keyed configuration at the ends of the foam matrix, but a similar configuration can also be employed on one or both side edges of the matrix and will fall within the scope of this patent.

The foam matrix will be available in varying lengths and widths with the width determined by the number and size of arched segments. Termination units will be available to insert and can be engaged by pins or similiar means for engagement in place into the concave troughs between the two sidewalls at any locations desired to end the form system. A thin section of foam or other suitable material, having the same shape of the termination unit, can also be inserted adjacent to the termination units and left in place to work as an expansion joint when the termination units have been removed and another section is being setup to pour. An alternate mode of the termination unit and expansion joint can be a rectangular metal piece with a sharp edge to be pressed into the foam arch segments, as a means to hold it in a fixed position which would not require the pin or stake.

On the underside of the foam matrix is a plurality of transverse channels with tapered sides that expand to the outer surface. Where the transverse channels and the upper concave troughs intersect, an orifice allows the fluid concrete to pass through filling the transverse channels and making contact with the ground. By minimizing the contact to the ground by the concrete and having the majority of the surface area of the concrete in contact with the foam surface, the water content of the concrete is maintained much longer than in the conventional processes where the moisture can pass into the ground through the entire lower surface. Slowing the curing time of the concrete has the result of improving quality and minimizing cracking. The unique arch in the concrete created by the arched foam segment is the key to making the concrete equal to or greater in strength than concrete constructed in a conventional manner while using considerably less concrete. The smooth surface of the arched segment and the concave troughs minimize stress risers that would precipitate cracking of the concrete material. Of course, other shapes such as octagons, rectangles, pentagons, or any shape which is calculated to handle the intended load, might be employed for the foam segment and any and all such shapes are anticipated by this application. However, the current preferred mode of the device employs the arched shape due to its superior load-bearing characteristics.

To understand the theory of the unique arched segments, it is best to review the history and theory of the arch structure. It was inevitable that the arch form should dominate the early history of building as without the availability of a material capable of taking significant tensile stresses, a predominantly compressive system was the only means of forming large spans, hence early structural and architectural forms were primarily based on columns, arches, and domes. Structural efficiency is attributed to the curvature of the arch, which transfers vertical loads laterally along the arch to the abutments at each side. The transfer of vertical forces gives rise to both horizontal and vertical reactions at the abutments. The curvature of the arch and the restraint of the arch by the abutments cause a combination of flexural stress and axial compression. The arch depth, rise and configuration can be manipulated to keep stresses primarily compressive. The compressive loads on the concrete surface in the modular forming system are translated in a uniform manner to the compacted surface of the ground by the means of the transverse channels that contain concrete. A vibratory float or similar apparatus may be used to flatten the surface and aid in settling the concrete into the crevices of the matrix of the modular concrete form system. Additional strength may be added by inserting a number of pieces of steel re-bar into the concave troughs and transverse channels. The concrete in the transverse channels is allowed to extend past the edge of the sidewalk or slab increasing the structural strength of the surface while being covered with the soil adjacent to the edge of the concrete. A wide variety of concrete mixes and sizes of aggregate are available to increase the density of the concrete material resisting the compressive forces.

With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of this invention.

FIG. 1A is a partially exposed view of a typical concrete wall being formed.

FIG. 1B is a top view of a typical concrete mold.

FIG. 2A is a side view of an embodiment of an interior mold form, according to the present invention.

FIG. 2B is a side view of an embodiment of an interior mold form, at 90 degrees to FIG. 2A, according to the present invention.

FIG. 2C is a perspective view of an embodiment of an interior mold form and reinforcing bars, according to the present invention.

FIGS. 3A through 3F illustrate an embodiment of a process for casting concrete, according to the present invention.

FIGS. 4A and 4B are cross sections (at right angles) of an embodiment of a concrete structure, according to the present invention.

FIG. 4C is a perspective view of an embodiment of a cast structure, according to the present invention.

FIG. 5 is a perspective view of an embodiment of an interior form with trapezoidal structure, according to the present invention.

FIG. 6 is a perspective view of an embodiment of an interior mold form with bumps within a concrete structure cast in a horizontal inclination, according to the present invention.

FIG. 7 is a perspective view of an embodiment of an interior mold form having ridges on one side within a concrete structure cast in a horizontal inclination, according to the present invention.

FIG. 8 depicts an exploded perspective view of the modular concrete form system with foam matrix, the termination unit and expansion joint along with an anchor pin or stake supporting means.

FIG. 9 depicts an exploded perspective view of the modular concrete form system with the alternate embodiment of a metal termination unit.

FIG. 10 depicts a perspective view of the under side of the modular concrete form system.

FIG. 11 depicts a side elevation of the modular concrete form system matrix.

FIG. 12 depicts an end view of the modular concrete form system matrix.

FIG. 13 depicts an end view of the termination unit.

FIG. 14 depicts a section through one of the arched segments illustrating the compressive stresses involved when forces are exerted on the surface of the concrete.

FIG. 15 depicts a perspective view of a simpler version of the modular concrete form system which provides for interlocking with adjacent matrix units create a form for cementitious material.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in conjunction with the accompanying drawings which are incorporated in and form a part of this specification, illustrating embodiments of the invention serve to explain the principles of this invention.

FIG. 2A is a side view of an embodiment of an interior mold form, according to the present invention. In some embodiments, form 200 is cut from a thin block (a right rectangular prism) having two large flat faces (sides). Because many structures are walls (or wall-like), it is convenient to describe embodiments of form 200 in terms of constructing walls. However, those skilled in the art will recognize that form 200 can be applied to many different structures of different shapes and sizes.

In some embodiments, form 200 will resemble a relatively thin sheet, having two major sides (surfaces). For purposes of illustration, an x-axis, which will be “horizontal” in some embodiments, is defined along one side of form 200, parallel to its surface. A y-axis, which will be “vertical” in some embodiments, is defined along the other long side of form 200, parallel to that surface, and perpendicular to the x-axis. A z-axis is defined through form 200, being normal to the surfaces (sides). While the terms “horizontal” and “vertical” are used to illustrate embodiments, because typical vertical walls are commonly cast, such terms are not intended as limiting. In application, embodiments of form 200, related processes, and structures in which it is used, may take on many shapes, orientations, and contours, which may or may not be symmetric, planar, or aligned with gravity.

As shown in FIG. 2A (looking along the x-axis at the y-z plane), in some embodiments, one face 201 of form 200 has roughly semi-cylindrical ridges 202 running along the x-axis. The term “semi-cylindrical” is to be broadly interpreted, and includes sections of a cylinder of different lengths and angular extent, as shown in FIG. 2A. Base 203 of each ridge 202 extends the shape of ridge 202 beyond a half cylinder, giving it a cross section, which is roughly a hemisphere with a rectangular base, an arch-shape. In some embodiments, ridges 202 are separated by troughs 204, which also run along the x-axis. Troughs 204 may be different shapes, for example, roughly rectangular or curved around the re-bar.

FIG. 2B is a side view of an embodiment of an interior mold form, at 90 degrees to FIG. 2A, according to the present invention. As shown in FIG. 2B, second face 205 of form 200 has ridges 206 running along the y-direction. Similar to first face 201, ridges 206 have base portions 207, and troughs 208 separate ridges 206. Thus, looking in the z-direction the x and y ridges 202, 206 and x and y troughs 204, 208 cross. In some embodiments, troughs 204 and 208 are deep enough (i.e., bases 203 and 207 are deep enough) such that they intersect inside form 200.

FIG. 2C is a perspective view of an embodiment of an interior mold form and re-bar, according to the present invention. Intersections 220 of x-troughs 204 and y-troughs 208 form holes 220, substantially extending through form 200.

Referring to FIGS. 1, 2A, and 2B, when concrete is to be cast around re-bar 106 and 108, horizontal re-bar 106 lies in troughs 204, and vertical re-bar 108 lies in troughs 208, crossing at intersections 220 of FIG. 2C. Because intersections 220 extend through form 200, re-bar 108 and 106 can be tied (if desired) through intersections 220. In some embodiments wire ties are used. As those skilled in the art will recognize, a tying machine with a long nose can be used to facilitate tying. Those skilled in the art will also recognize that not every intersection of re-bar 106 and 108 needs to be tied.

Referring to FIGS. 2A and 2B, in some embodiments, holes 210 are formed in form 200. In some embodiments, holes 210 are formed by cutting into form 200 along lines 212, because holes 210 may be longer than a conventional drill bit. Holes 210 can be cut along x and y directions or along any other convenient directions through form 200.

In some embodiments, plastic rods 214 are inserted in holes 210 of form 200 to aid in positioning form 200 with respect to re-bar 106 and 108. Plastic rods 214 can stop form 200 from sliding too far onto re-bar 106 or 108. Plastic rods 214 can also supply means of tying form 200 onto re-bar. In some embodiments, rods 214 are not used, and in some embodiments there are fewer rods than pieces of re-bar 106 and 108.

In some embodiments, form 200 is made from 2-lb polystyrene. 2-lb polystyrene has desirable compression (approximately 20 pound per square-inch) and machining properties. Form 200 is stiff enough to resist being crushed by the mass of concrete. Depending on the scale of the casting to be performed other weights of polystyrene may be acceptable, if they provide sufficient compression resistance. In some embodiments, form 200 is made from other lightweight, inexpensive materials, such as fiberglass, composite carbon/graphite, plastic, or other weights of polystyrene. For casting materials other than concrete, form 200 may be formed from materials resistant to adverse conditions during casting (e.g., extreme pressure, chemical damage, high temperatures).

In some embodiments, form 200 is cut from a 3 by 4 by 8-foot block of 2-lb polystyrene. Billets are typically manufactured in 3 by 4 by 24-foot sizes, and 8-foot lengths are convenient to cut from such a billet (also being roughly the size of typical freeway sound barrier segments). Of course, different applications will require different sizes and shapes of concrete castings, so given dimensions are exemplary. As an example of relative dimensions, in some embodiments form 200 is 3 9/16-inches thick. Ridges 202, 206 (and therefore troughs 204, 208) have a period of 4-inches. Each ridge 202, 206 has a semi-cylindrical diameter of 2⅞-inches (radius of 1 7/16-inches) and a 7/8-inch base height, for a total height of 2½-inches. Each trough has a width of 1⅛-inches and a depth of 2½-inches (leaving 1 1/16-inches of material). For a form of these exemplary dimensions, external mold sides 102 are placed so as to create a thickness of 11/16-inch of concrete between each of mold sides 102 and form 200.

FIGS. 3A through 3F illustrate embodiments of a mold and a process for casting concrete, according to the present invention. In FIG. 3A, form blank 200′ is ready to be cut into form 200.

In FIG. 3B, form 200 is shown after ridges 202 and troughs 204 have been machined into it. It has also been provided with plastic rods 214.

In FIG. 3C vertical pieces of re-bar 108 are set up and form 200 is inserted over them. Horizontal re-bar 106 is added, and (if desired) ties 110 are applied.

FIG. 3D shows the completed form and rebar.

FIG. 3E shows the completed form 200 and rebar 106, 108 inserted between mold barriers 102 to form mold 300. Those skilled in the art will appreciate that all sides of mold 300 are sealed with additional plywood, plastic sheets, earth, previously cast sections, or another material to prevent mix 120 from leaking out.

FIG. 3F illustrates material 120 poured into mold 300, around form 200.

While a vertical mold is exemplary, it is well known to those skilled in the art, that walls for concrete buildings can be cast in a horizontal orientation, on the ground, before being raised into a vertical position. In such a process, all the re-bar (and the x- and y-axis) would be literally horizontal during casting and curing. However, it is convenient to refer to re-bar 106 and 108 as being “vertical” or “horizontal,” and such terms are not intended as limiting.

By means of using form 200, a concrete structure can be created, which is lighter than a solid concrete structure of equal size and strength.

Those skilled in the art will recognize that mold 300 and form 200 need not be rectangular as they can be oval or oddly shaped. Further, those skilled in the art will recognize that mold 300 and form 200 need not be planar, although many applications use planar shapes. Given that modern architecture makes use of many curved and irregular surfaces, embodiments of form 200, mold 300, and the molding process will make use of forms and molds of many different shapes, sizes, and contours.

Further, those skilled in the art will recognize that while re-bar 106 and 108 are commonly used in concrete structures, re-bar is not essential to all embodiments of casting processes or resulting structures. Therefore, in some embodiments of the device herein disclosed, there is no re-bar. In some embodiments, structural integrity is reinforced by means other than inserting re-bar 106 and 108 (e.g., inserting graphite fibers).

FIGS. 4A and 4B are cross sections of an embodiment of a concrete structure, according to the present invention. FIG. 4A is an x-z view of concrete structure 400. Half 410 of structure 400 can be seen to have chambers 412 running through it in the y-direction. In some embodiments, form 200 is left in-place after casting concrete 120, so that form 200 remains in chambers 412. Similarly, half 420 of structure 400 can be seen to have chambers 422 running through it in the x-direction, also filled with form 200.

While chambers 412 and 422 are not filled with concrete, the arched semi-cylindrical shape of chambers 412 and 422 bear stresses within structure 400 more efficiently than solid concrete. Because chambers 412 and 422 are crossed, each of the halves 412 and 422 resists stresses along the different axis. Therefore, the double-arched hollows within structure 400 provide superior strength to solid concrete. Further, by creating structures of lighter weight, each structure in, for example a building, needs to support less weight of itself and other structures, thereby making the entire building more efficiently constructed, than if it were made of solid walls.

FIG. 4C is a perspective view of an embodiment of a cast structure, according to the present invention. As in FIGS. 4A and 4B, it can be seen that structure 400 is formed with interior arches 413 on side 410 running in the y direction and with arches 423 on side 420 running in the x direction.

FIG. 5 is a perspective view of an embodiment of an interior form with trapezoidal structure, according to the present invention. Referring to FIGS. 2-4, some embodiments make use of arch-shaped, semi-circular ridges 202, 206 in form 200, forming arches 412, 423 in structure 400. Interior mold form 500 (shown in FIG. 5) makes use of trapezoidal ridges 502 (having trapezoidal cross-sections). Similar to the semi-circular arch shapes in ridges 202, 206 of form 200, the trapezoidal shape of ridges 502 of form 500 also provides strength in the resulting structure. Those skilled in the art will recognize other ridge configurations that may differ in geometry (e.g., geodesic), but which perform the function of providing structure 400 with material strength y providing a stable internal structure.

FIG. 6 is a perspective view of an embodiment of an interior mold form with bumps within a concrete structure cast in a horizontal inclination, according to the present invention. Mold form 600 includes hemispherical bumps 602, which displace material 120 during casting. In some embodiments, mold form 600 is used to cast concrete for roadways. The shape of bumps 602 results in the formation of arches in the resulting structure. In some embodiments, bumps 602 are on one side of form 600. In some embodiments form 600 is used for horizontal structures (e.g., roads, counter-tops), where the structure is designed to bear the vertical stress of 1 objects pressing down on it.

In some embodiments, form 600 includes base 610, having thickness 612. In some embodiments, thickness 612 is made thick enough to provide convenient strength to mold form 600 for handling and transportation. In some embodiments, thickness 612 is very thin, only thick enough to hold bumps 602 in place during casting. In some embodiments thickness 612 vanishes, and bumps 602 are held in place by wires, rods, or other means, or held in place by friction against the surface under them. In some embodiments, bumps 602 are an array of discrete interior forms.

In some embodiments, material 120 is cast around form 600 and re-bar 106 and 108. In some embodiments, lower layer 620 of material 120 has a thickness of approximately 2-inches, form thickness 612 is approximately 2-inches, making form and upper layer 622 of material 120 approximately 12 inches thick. Total thickness 624 is approximately 16-inches.

In some embodiments, a structure, such as a roadway, is formed by preparing the ground, then pouring a thin layer of concrete. Form 600, along with rebar 106, is placed on top of the first layer of concrete, and a thicker main layer is poured.

FIG. 7 is a perspective view of an embodiment of an interior mold form having ridges on one side within a concrete structure cast in a horizontal inclination, according to the present invention. In some embodiments, material and weight can be saved by using an interior form 700 with ridges 702 on only one side 704. Provided that the structure cast with form 700 will have sufficient strength for its intended purpose (while having an asymmetric interior structure) mold form 700 is simple to make and will save on material costs. Referring to FIGS. 2A-2B, in some embodiments ridges 702 are semi-circular, arch shaped. Referring to FIG. 5, in some embodiments ridges 702 are trapezoidal. In some embodiments, ridges 702 have other structural cross sections, shapes, or contours.

FIG. 8-15 depicts an exploded perspective view of another particularly preferred mode of the disclosed invention herein featuring a modular concrete form system 10 with the foam matrix 12, a termination unit 14 and expansion joint 16 along with an anchor pin 18 or wood stake 20 or similiar elongated member for use as a supporting means. This embodiment is particularly easy to use by both trained and untrained workers and would provide great utility to homeowners who are unfamiliar with the concrete forming process. Employing a number of matrixes, the construction of a form to pour a sidewalk or patio or other paving type construction, is made easier for a professional familiar with the process, and well within reach of the novice or homeowner unfamiliar with constructing form. The foam matrix 12 will be constructed of polypropylene foam, polyethylene foam, Styrofoam, PVC foam, urethane foam, epoxy foam or any other foam suitable for the application. A quantity of anchor pins 18 or wood stakes 20 or other means to secure all the matrix 12 and engaging components in place will be generally required. The anchor pins 18 will also be used to anchor the termination units 14 into position at the end of the structure or the end of a portion of the structure to be poured.

The foam matrix 12 employs two sidewalls 22 and 24 preferably with beveled edges 26 communicating between the top edge 30 of the sidewall 22 and the planar surface 28 on the exterior of the sidewall 22 and the interior of the sidewall 22. The thickness of the finished cast structure is determined by the height of the sidewalls 22 and 24. In an embodiment of the device 10 somewhat less functional but still an improvement, the sidewalls 22 and 24 might be left of the matrix 12 and wooden or other structural members employed instead. While not as functional as providing built-in sidewalls, this embodiment would still provide the aforementioned benefits of the arched matrix 12 engaged with the layered concrete.

The top side of the matrix 12 has disposed on it, a plurality of arched segments 32 separated by concave troughs 34 and are used to create the central cavity 36 of the foam matrix 12. The width of the foam matrix 12 will be determined by the number and diameter of the arched segments 30. The foam matrix 12 will come in a variety of lengths and widths with a modified tongue 38 and groove 40 or other cooperatively engaging connection means 42 at the distal ends 44 and 46 of the matrix 12 to connect it to an adjacent matrix 12 to thereby create as long a modular concrete form system 10 as desired. While a keyed, or tongue and groove means of engagement of adjacent matrix components is shown, those skilled in the art will realize that other configurations that engage adjacent matrix units can be employed and all such means of engagement are anticipated. An angular recess 48 and an angular extension 50 form the current preferred mode of the locking portion of the connection means 42 and they are placed inline with the arched segments 32 and the sidewalls 22 and dimensioned in a fashion to continue both when joined to an adjacent matrix 12 and the smooth planar surfaces 28 as well as the smooth exterior surface of the arched segments 32.

On the underside 52 of the foam matrix 12 are a plurality of transverse channels 54 which in the current preferred mode have tapered sides 56 that expand to the underside outer surface 58. Where the transverse channels 54 and the upper concave troughs 34 intersect, a plurality orifices 60 provide a means for communication of the fluid concrete from the troughs 34 to the travers channels 54 thereby filling the transverse channels 54 with concrete during the pour, and providing contact with the ground to the concrete to support the overhead structures.

The termination units 14 will be constructed of polypropylene foam, polyethylene foam, Styrofoam, PVC foam, urethane foam, epoxy foam or any other foam suitable for the application. The termination unit 14 will have two distal ends 62 and 64 that fit tightly between the internal planar surfaces 28 of the sidewalls 22 and 24 of the foam matrix 12 when fixed into position. A plurality of concave trough mating segments 66 seal the concave troughs 34 between the arched segments 32. The top surface 68 of the termination unit 14 will be flush with the top edges 30 of the sidewalls 22 and 24 when properly fixed in position to allow for the purpose of finishing the concrete surface along all of the edges. The expansion joint 16, if employed, will have a similar configuration to the termination units 14 with distal ends 70 and 72 along with a plurality of concave trough mating segments 74.

An alternate embodiment of a termination unit 14 shown in FIG. 9 is also employed as an expansion joint 16 and consists of a rectangular sheet of galvanized metal 76 with a sharp edge 78 and distal ends 80 and 82 that can be pressed down into the arched segments 32 with the top surface 84 either flush or below the top edges 30 of the matrix 12. This sheet of galvanized metal 76 may also be used in a similar fashion as a substitute for the termination units 14 to be inserted at each end of the concrete pour and also may be used intermittently along the length of the pour as expansion joints 16.

FIG. 10 depicts a perspective view of the matrix underside 52 displaying the plurality of transverse channels 54 and the orifices 60 created by the intersection of the concave troughs 34. The orifices 60 allow the fluid concrete mixture to flow into the transverse channels 54 extending past the matrix sidewalls 22 and 24 into the subsoil 86.

FIG. 11 depicts a side elevation of the foam matrix 12 illustrating the sidewall 22 with the connection means 42 having a tongue 36 and angular recess at the distal end 46 and the mating groove 40 and angular extension 50. Along the top edge 30 is a beveled edge that extends the full length of the sidewall 22. A plurality of transverse channels 54 are shown with tapered sides 56 along the matrix underside 52.

FIG. 12 depicts an end view of the matrix 12 illustrating the two sidewalls 22 and 24 with the plurality of arched segments 32 separated by the concave troughs 34.

FIG. 13 depicts an end view of the termination unit 14 and how it mates with the foam matrix 12 by having the concave trough mating segments 66 fill the gaps of the concave troughs 34. The distal ends 62 and 64 of the termination unit 14 fit tightly against the matrix sidewall internal surfaces 28 with the top surface 68 flush with the top edges 30 of the matrix sidewalls 22 and 24. Once the cement has set sufficiently for the form composed of matrix 12 segments to be removed about the perimeter of the formed concrete structure, the sidewalls 22 being formed of foam or other aforementioned material, may be broken off to leave just the concrete surface at ground level. The sidewalls 22 and 24 may also be rendered easily frangible by the addition of a serration or thin perforation or slit 23 at a base edge which does not go completely through the sidewall, to provide an easy and clean separation from the rest of the matrix 12 once the concrete is cured sufficiently. When placed on the outside edge, there is virtually no loss of strength to hold the cementitious material inside.

FIG. 14 depicts a section through one of the arched segments 32 illustrating the compressive stresses involved when forces 88 are exerted on the surface 90 of the concrete 92 and transfers vertical loads laterally along the arch to the area of the concave trough 34 at each side. The transfer of vertical forces gives rise to both horizontal and vertical reactions in these areas. The curvature of -the arched segments 32 and the restraint of the arch by the concave troughs 34 cause a combination of flexural stress and axial compression 94, which is then conducted through the concrete in the orifices 60 to the concrete within the transverse channels 54 and then onto the compacted subsoil 86. A segment 96 of the concrete 92 from the transverse channels 54 extends past the sides 98 of the finished portion to be covered with the surface soil 99.

Finally, as noted above, in a simpler embodiment which does not offer the utility of a material core formed into the cured cementitious material, FIG. 15 depicts a perspective view of the modular concrete form system which provides for means to engage one end of the foam matrix 12 with the other end of an adjacent foam matrix 12. The means for cooperative engagement shown is a tongue 38 and groove 40 which would overlap and form a planar bottom surface surrounded by sidewalls 22 and 24 and endwalls 62 which would be adapted for engagement on both ends. Also shown is the noted optional perforation or slit 23 which would allow for easy removal of the sidewalls 22 and 24 in the unitary structure form of the matrix 12 once the cementitious material has cured sufficiently. While this embodiment of the device lacks the arched segments 32 disposed on the top side of the sheet of material forming the matrix 12 it could still have the traverse channels 54 communicating through the orifices 60 or in an even simpler version, could eliminate the transverse channels 54 also. While eliminating both of the preferred structures of the channels 54 and the arched segments 32 would eliminate the aforementioned utility and benefits thereof, the interlocking matrix 12 even in such a simple embodiment would yield great utility especially to inexperienced people wishing to form sidewalks and patios since they need only interlock the matrixes and then pour in the cementitious material.

While concrete casting is exemplary of some embodiments of the present invention, those skilled in the art will recognize that embodiments of the forms and processes herein described are also applicable to other materials on larger or smaller scales. Such materials may include structural plastics, graphite epoxies, metals, and many other materials, where it is desirable to reduce the volume of material required to form a completed structure.

Additionally, the method and apparatus for casting structures employing the modular concrete form system shown in the drawings and described in detail herein, discloses arrangements of elements of particular construction and configuration for illustrating preferred embodiments of structure and method of operation of the present invention. It is to be understood, however, that elements of different construction and configuration and other arrangements thereof, other than those illustrated and described may be employed for providing a modular concrete form system in accordance with the spirit of this invention, and any and all such changes, alternations and modifications, as would occur to those skilled in the art, are considered to be within the scope of this invention as broadly defined in the appended claims.

Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way. 

1. A mold form apparatus for casting of structures from cementitious material, comprising: a sheet of material having a top surface, a bottom surface, a first side edge, a second side edge, a first end, and a second end; said sheet of material dimensioned for placement in an installed position within a recess defined by two sidewalls communicating with two endwalls; and whereby said sheet of material in said installed position provides communication of said cementitious material deposited in said recess from said trough segments to said channels and thereafter is fixed in position therebetween, upon curing of said cementitious material.
 2. The mold form apparatus of claim 1 additionally comprising: said two sidewalls being comprised of a first sidewall disposed along said first side edge, and a second sidewall disposed along said second side edge in a unitary structure with said sheet of material.
 3. The mold form apparatus of claim 2 additionally comprising: each of said pair of endwalls being adapted for removable engagement with said sheet of material, at either said first end or said second end, whereby said pair of endwalls are removably engageable to said sheet of material to a communication with said sidewalls to form said recess between said sidewalls and said endwalls.
 4. The mold form apparatus of claim 2 further comprising: a first plurality of substantially parallel ridges disposed on said bottom surface between said first end and said second end; a plurality of channels disposed between said first plurality of substantially parallel ridges; a plurality of apertures communicating with said channels through said top surface; and whereby said sheet of material in said installed position provides communication of said cementitious material deposited in said recess to said channels through said apertures and thereafter is fixed in position therebetween, upon curing of said cementitious material.
 5. The mold form apparatus of claim 3 further comprising: a first plurality of substantially parallel ridges disposed on said bottom surface between said first end and said second end; a plurality of channels disposed between said first plurality of substantially parallel ridges; a plurality of apertures communicating with said channels through said top surface; and whereby said sheet of material in said installed position provides communication of said cementitious material deposited in said recess to said channels through said apertures and thereafter is fixed in position therebetween, upon curing of said cementitious material.
 6. The mold form apparatus of claim 4 further comprising: a second plurality of substantially parallel ridges disposed on said top surface between said first end and said second end; a plurality of trough segments disposed between said first plurality of substantially parallel ridges, said trough segments communicating with said plurality of apertures; and whereby said sheet of material in said installed position provides communication of said cementitious material deposited in said recess from said trough segments to said channels and thereafter is fixed in position therebetween, upon curing of said cementitious material.
 7. The mold form apparatus of claim 5 further comprising: a second plurality of substantially parallel ridges disposed on said top surface between said first end and said second end; a plurality of trough segments disposed between said first plurality of substantially parallel ridges, said trough segments communicating with said plurality of apertures; and whereby said sheet of material in said installed position provides communication of said cementitious material deposited in said recess from said trough segments to said channels and thereafter is fixed in position therebetween, upon curing of said cementitious material.
 8. The mold form apparatus of claim 1 additionally comprising: a plurality of said sheets of material; and each of said plurality of sheets of material adapted at said first end, for cooperative engagement with a respective said second end of an adjacent one of said plurality of said sheets of material, whereby a plurality of said sheets of material may be engaged with each other, end to end, to define an elongated said mold form.
 9. The mold form apparatus of claim 2 additionally comprising: a plurality of said sheets of material; and each of said plurality of sheets of material adapted at said first end, for cooperative engagement with a respective said second end of an adjacent one of said plurality of said sheets of material, whereby a plurality of said sheets of material may be engaged with each other, end to end, to define an elongated said mold form.
 10. The mold form apparatus of claim 3 additionally comprising: a plurality of said sheets of material; and each of said plurality of sheets of material adapted at said first end, for cooperative engagement with a respective said second en, of an adjacent one of said plurality of said sheets of material, whereby a plurality of said sheets of material may be engaged with each other, end to end, to define an elongated said mold form.
 11. The mold form apparatus of claim 4 additionally comprising: a plurality of said sheets of material; and each of said plurality of sheets of material adapted at said first end, for cooperative engagement with a respective said second en, of an adjacent one of said plurality of said sheets of material, whereby a plurality of said sheets of material may be engaged with each other, end to end, to define an elongated said mold form.
 12. The mold form apparatus of claim 5 additionally comprising: a plurality of said sheets of material; and each of said plurality of sheets of material adapted at said first end, for cooperative engagement with a respective said second en, of an adjacent one of said plurality of said sheets of material, whereby a plurality of said sheets of material may be engaged with each other, end to end, to define an elongated said mold form.
 13. The mold form apparatus of claim 6 additionally comprising: a plurality of said sheets of material; and each of said plurality of sheets of material adapted at said first end, for cooperative engagement with a respective said second en, of an adjacent one of said plurality of said sheets of material, whereby a plurality of said sheets of material may be engaged with each other, end to end, to define an elongated said mold form.
 14. The mold form apparatus of claim 7 additionally comprising: a plurality of said sheets of material; and each of said plurality of sheets of material adapted at said first end, for cooperative engagement with a respective said second en, of an adjacent one of said plurality of said sheets of material, whereby a plurality of said sheets of material may be engaged with each other, end to end, to define an elongated said mold form.
 15. The mold form apparatus of claim 1 additionally comprising: a plurality of said sheets of material each adapted at one of said first or said second side edges of said sheet of material, for cooperative engagement with an adjacent one of said first or second side edges on another of said plurality of sheets of material; each of said plurality of sheets of material so engaged, having said endwalls engageable at respective first and second ends; and whereby said recess can be formed in widths defined by the number of said plurality of said sheets of material engaged at adjacent side positions.
 16. The mold form apparatus of claim 4 additionally comprising: said mold form apparatus provided in a kit having a plurality of said sheets of material adapted for cooperative engagement with each other; said kit also including a plurality of said endwalls; and means for fixing said mold form apparatus in place to an underlying surface.
 17. The mold form apparatus of claim 5 additionally comprising: said mold form apparatus provided in a kit having a plurality of said sheets of material adapted for cooperative engagement with each other; said kit also including a plurality of said endwalls; and means for fixing said mold form apparatus in place to an underlying surface.
 18. The mold form apparatus of claim 6 additionally comprising: said mold form apparatus provided in a kit having a plurality of said sheets of material adapted for cooperative engagement with each other; said kit also including a plurality of said endwalls; and means for fixing said mold form apparatus in place to an underlying surface.
 19. The mold form apparatus of claim 7 additionally comprising: said mold form apparatus provided in a kit having a plurality of said sheets of material adapted for cooperative engagement with each other; said kit also including a plurality of said endwalls; and means for fixing said mold form apparatus in place to an underlying surface.
 20. The mold form apparatus of claim 7 additionally comprising: means to render said sidewalls frangible at a bottom edge of said sidewalls, whereby said sidewalls may be easily separated from said sheet of material. 